Methods, systems, and apparatus for providing variable illumination

ABSTRACT

Digital Control Ready (DCR) is a two-way open standard for controlling and managing next-generation fixtures. A DCR-enabled lighting fixture responds to digital control signals from a separate digital light agent (DLA) instead of analog dimming signals, eliminating the need for digital-to-analog signal conditioning, fixture-to-fixture variations in response, and calibration specific to each fixture. In addition, a DCR-enabled lighting fixture may also report its power consumption, measured light output, measured color temperature, temperature, and/or other operating parameters to the DLA via the same bidirectional data link that carries the digital control signals to the fixture. The DLA processes these signals in a feedback loop to implement more precise lighting control. The DCR-enabled lighting fixture also transforms AC power to DC power and supplies (and measures) DC power to the DLA via a DCR interface. These features enable intelligent, networked DCR lighting systems operate with lower power (energy) consumption, greater flexibility, and simpler installation than other intelligent lighting networks.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application claims priority, as a bypass continuation under 35U.S.C. §120, to PCT/US2013/031790, filed on Mar. 14, 2013, which claimsthe benefit, under 35 U.S.C. §119(e), of:

-   U.S. Provisional Patent Application No. 61/612,580, filed on Mar.    19, 2012, entitled “Lighting Fixture”;-   U.S. Provisional Patent Application No. 61/697,635, filed on Sep. 6,    2012, entitled “Digital Light Agent;” and-   U.S. Provisional Patent Application No. 61/762,592, filed on Feb. 8,    2013, entitled “Digital Light Agent.” Each of these applications is    hereby incorporated herein by reference in its respective entirety.

BACKGROUND

Intelligent lighting systems combine solid-state light sources, embeddedsensors and controls, and low-cost pervasive networking to create anintegrated illumination system which is highly responsive to itsenvironment. Benefits of some or all such systems may include, but arenot limited to, a much higher quality of light tailored specifically touser needs and significant energy savings compared to legacy lightingsystem technologies.

SUMMARY

Embodiments of the present invention include a system for providingvariable illumination to an environment. In one embodiment, the systemincludes at least one digital control ready (DCR) lighting fixture,disposed in a first location of the environment, to provide the variableillumination to at least a portion of the environment, and at least onedigital light agent (DLA), disposed in a second location of theenvironment and operably coupled to the at least one DCR lightingfixture, to control the at least one DCR lighting fixture in response toat least one change in the environment.

In at least one embodiment, the DCR lighting fixture comprises a fixturehousing that contains and/or supports at least one light source (e.g.,one or more light-emitting diodes (LEDs)), at least one light sourcedriver, an alternating current (AC) power input, a power converter, apower meter, and a fixture input/output bus. In operation, the lightsource generates the variable illumination in response to the digitalcontrol signal from the DLA. The light source driver, which is operablycoupled to the light source, powers the light source according to thedigital control signal, using AC power from the AC power input, which isoperably coupled to the light source driver and the power converter. Thepower converter converts the AC power to direct current (DC) power at avoltage of less than or equal to +60 V (e.g., +40 VDC, +24 VDC, or +12VDC) for powering the DLA. The power meter, which may be coupled to thelight source driver, the AC power input, and/or the power converter,measures the DCR lighting fixture's power consumption. And the fixtureinput/output bus, which is operably coupled to the light source, thepower converter, and the power meter, receives the digital controlsignal from the DLA and provides at least one digital reporting signalrepresentative of the DCR lighting fixture's power consumption and/orlight output to the DLA. For instance, this digital reporting signal mayinclude information about the DCR lighting fixture's power consumption,energy consumption, AC power quality, color temperature, lightintensity, and/or temperature. The fixture input/output bus alsoprovides DC power to the DLA.

In certain embodiments, the DLA includes a DLA housing that holds and/orsupports at least one sensor (e.g., an occupancy sensor, a temperaturesensor, an ambient light level sensor, and a clock), a memory, aprocessor, a DLA input/output bus, and a network interface (e.g., anantenna). In operation, the sensor provides at least one sensor signalrepresentative of change(s) in the environment, such as changes inoccupancy, ambient light level, temperature, time, etc. The memorystores at least one rule governing a change in the variable illuminationprovided by the DCR lighting fixture based on the change(s) in theenvironment. The processor, which is operably coupled to the sensor andto the memory, generates the digital control signal based on the rule(s)and the sensor signal and transmits the digital control signal to theDCR lighting fixture via the DLA input/output bus. The DLA input/outputbus also receives the digital reporting signal and the DC power from theDCR lighting fixture. And the network interface, which is operablycoupled to the processor, provides data representative of the digitalreporting signal, the digital control signal, and/or sensor signal to auser.

Some embodiments of the inventive lighting systems include a cable thatconnects the fixture input/output bus to the DLA input/output bus. Thiscable and the input/output buses may be compatible with a localinterconnect network (LIN) standard, a controller area network (CAN)standard, a KNX standard, and/or a digital addressable lightinginterface (DALI) standard. In some cases, the lighting system includes asecond DCR lighting fixture operably coupled to the DLA via a secondcable and, optionally, a third DCR lighting fixture operably coupled tothe DLA via a third cable coupled to the second DCR lighting fixture.

Examples of the fixture input/output bus and the DLA input/output busmay each comprise: a respective power port for the second portion of theDC power; a respective common port for a reference voltage level; and atleast one respective data port for the at least one digital reportingsignal and the at least one digital control signal. The fixtureinput/output bus and the DLA input/output bus may each be compatiblewith a local interconnect network (LIN) standard, a controller areanetwork (CAN) standard, a KNX standard, and/or a digital addressablelighting interface (DALI) standard.

Exemplary DCR lighting fixtures may also include at least one sensor anda processor coupled to the sensor. The sensor measures at least onefixture parameter, such as a temperature of the light source (e.g.,LED), a light source bias voltage, a light source operating current, alight source color temperature, and/or a light source color. Theprocessor receives this fixture parameter measurement from the sensorand transmits a measurement signal representative of the fixtureparameter to the DLA via a data port in fixture input/output bus.

Additional embodiments of the present invention include a method ofilluminating an environment with variable illumination from at least oneDCR lighting fixture disposed in a first location within theenvironment. One example of this method comprises sensing at least onechange in the environment (e.g., a change in occupancy, environmentaltemperature, and/or ambient light level) at a DLA disposed in a secondlocation within the environment. The DLA or other processor determines achange in the variable illumination from the DCR lighting fixture basedat least in part on the change in the environment and generates adigital control signal based at least in part on this change in thevariable illumination. The DLA transmits this digital control signal tothe DCR lighting fixture via at least one cable connected to aninput/output bus.

The DLA may also receive (DC) electrical power from the DCR lightingfixture via the cable and the input/output bus, e.g., at a voltage ofless than or equal to +40 VDC, +24 VDC, +12 VDC, etc. The DLA may alsoreceive a digital reporting signal representative of the DCR lightingfixture's power consumption via the cable and the input/output bus. Inthese cases, the DLA or other processor may determine the change in thevariable illumination based at least in part on the DCR lightingfixture's power consumption. And the DLA may transmit datarepresentative of the DCR lighting fixture's power consumption via anantenna or other wireless link.

For purposes of the present disclosure, the term “ambient light” refersto visible radiation (i.e., radiation whose wavelength is between about450 nm and about 700 nm) that pervades a given environment or space. Inother words, ambient light is the soft, indirect light that fills thevolume of the environment and is perceptible to a person within theenvironment.

Similarly, the term “ambient light level” refers to the illuminance, orluminous flux on a surface per unit area. The illuminance is a measureof how much the incident light illuminates the surface,wavelength-weighted by the luminosity function to correlate with humanbrightness perception. Luminous flux may be measured in lux (lumens persquare meter) or foot-candles.

The following U.S. published applications are hereby incorporated hereinby reference:

-   U.S. Pat. No. 8,138,690, issued Feb. 29, 2012, filed Jun. 25, 2010,    and entitled “LED-BASED LIGHTING METHODS, APPARATUS, AND SYSTEMS    EMPLOYING LED LIGHT BARS, OCCUPANCY SENSING, LOCAL STATE MACHINE,    AND METER CIRCUIT”;-   U.S. Pat. No. 8,232,745, issued Jul. 31, 2012, filed Apr. 14, 2009,    and entitled “MODULAR LIGHTING SYSTEMS”;-   U.S. Pat. No. 8,339,069, issued Dec. 25, 2012, filed Jun. 30, 2010,    and entitled “POWER MANAGEMENT UNIT WITH POWER METERING”;-   U.S. Pre-Grant Publication No. 2010-0296285-A1, published Nov. 25,    2010, filed Jun. 17, 2010, and entitled “SENSOR-BASED LIGHTING    METHODS, APPARATUS, AND SYSTEMS EMPLOYING ROTATABLE LED LIGHT BARS”;-   U.S. Pre-Grant Publication No. 2010-0301773-A1, published Dec. 2,    2010, filed Jun. 24, 2010, and entitled “LED-BASED LIGHTING METHODS,    APPARATUS, AND SYSTEMS EMPLOYING LED LIGHT BARS OCCUPANCY SENSING,    AND LOCAL STATE MACHINE”;-   U.S. Pre-Grant Publication No. 2010-0302779-A1, published Dec. 2,    2010, filed Jun. 24, 2010, and entitled “LED-BASED LIGHTING METHODS,    APPARATUS, AND SYSTEMS EMPLOYING LED LIGHT BARS, OCCUPANCY SENSING,    LOCAL STATE MACHINE, AND TIME-BASED TRACKING OF OPERATIONAL MODES”;-   U.S. Pre-Grant Publication No. 2010-0264846-A1, published Oct. 21,    2010, filed Jun. 28, 2010, and entitled “POWER MANAGEMENT UNIT WITH    ADAPTIVE DIMMING”;-   U.S. Pre-Grant Publication No. 2010-0295473-A1, published Nov. 25,    2010, filed Jun. 30, 2010, and entitled “LED LIGHTING METHODS,    APPARATUS, AND SYSTEMS INCLUDING RULES-BASED SENSOR DATA LOGGING”;-   U.S. Pre-Grant Publication No. 2010-0301768-A1, published Dec. 2,    2010, filed Jun. 30, 2010, and entitled “LED LIGHTING METHODS,    APPARATUS, AND SYSTEMS INCLUDING HISTORIC SENSOR DATA LOGGING”;-   U.S. Pre-Grant Publication No. 2012-0235579, published Sep. 20,    2012, filed Mar. 20, 2012, and entitled “METHODS, APPARATUS AND    SYSTEMS FOR PROVIDING OCCUPANCY-BASED VARIABLE LIGHTING”;-   U.S. Pre-Grant Publication No. 2012-0143357, published Jun. 7, 2012,    filed Nov. 4, 2011, and entitled “METHOD, APPARATUS, AND SYSTEM FOR    OCCUPANCY SENSING”;-   WO 2012/061709, published May 10, 2012, filed Nov. 4, 2011, and    entitled “METHOD, APPARATUS, AND SYSTEM FOR OCCUPANCY SENSING”;-   WO 2012/129243, published Sep. 27, 2012, filed Mar. 20, 2012, and    entitled “METHODS, APPARATUS AND SYSTEMS FOR PROVIDING    OCCUPANCY-BASED VARIABLE LIGHTING”; and-   PCT/US2012/63372, filed Nov. 2, 2012, and entitled “METHODS,    APPARATUS AND SYSTEMS FOR INTELLIGENT LIGHTING.”

It should be appreciated that all combinations of the foregoing conceptsand additional concepts discussed in greater detail below (provided suchconcepts are not mutually inconsistent) are contemplated as being partof the inventive subject matter disclosed herein. In particular, allcombinations of claimed subject matter appearing at the end of thisdisclosure are contemplated as being part of the inventive subjectmatter disclosed herein. It should also be appreciated that terminologyexplicitly employed herein that also may appear in any disclosureincorporated by reference should be accorded a meaning most consistentwith the particular concepts disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The skilled artisan will understand that the drawings primarily are forillustrative purposes and are not intended to limit the scope of theinventive subject matter described herein. The drawings are notnecessarily to scale; in some instances, various aspects of theinventive subject matter disclosed herein may be shown exaggerated orenlarged in the drawings to facilitate an understanding of differentfeatures. In the drawings, like reference characters generally refer tolike features (e.g., functionally similar and/or structurally similarelements).

FIG. 1 illustrates a conventional intelligent lighting system.

FIG. 2A illustrates an intelligent lighting system with a digitalcontrol ready (DCR) lighting fixture coupled to a DCR digital lightagent (DLA) according to embodiments of the present invention.

FIG. 2B illustrates a DLA that controls multiple DCR lighting fixturesvia a daisy-chain connection according to embodiments of the presentinvention.

FIG. 3 illustrates a DCR lighting fixture according to embodiments ofthe present invention.

FIG. 4 illustrates a DLA according to embodiments of the presentinvention.

FIG. 5A illustrates an intelligent lighting system with a conventionallighting fixture coupled to a DLA via a DLA fixture adapter (DLAFA)according to embodiments of the present invention.

FIG. 5B illustrates a DLA that controls multiple DCR lighting fixturesvia DLAFA in a daisy-chain connection with the DCR lighting fixturesaccording to embodiments of the present invention.

FIG. 6 illustrates a digital light agent fixture adapter (DLAFA), orsmart power pack, suitable for use with a DCR lighting fixture accordingto embodiments of the present invention.

FIGS. 7A-7D show exemplary power savings achieved by implementingmulti-level occupancy, task tuning, daylight harvesting, and schedulingresponses with a DCR intelligent lighting system according toembodiments of the present invention.

FIG. 8 is a pie chart that shows exemplary power savings distributedaccording to savings source with a DCR intelligent lighting systemaccording to embodiments of the present invention.

DETAILED DESCRIPTION

Following below are more detailed descriptions of various conceptsrelated to, and embodiments of, inventive systems, methods, andapparatus for providing variable illumination with digital control readylighting fixtures. It should be appreciated that various conceptsintroduced above and discussed in greater detail below may beimplemented in any of numerous ways, as the disclosed concepts are notlimited to any particular manner of implementation. Examples of specificimplementations and applications are provided primarily for illustrativepurposes.

Networked Lighting Systems

FIG. 1 shows a networked lighting system 100 suitable for illuminating awarehouse, cold-storage facility, office space, retail space, sportsvenue, school, residential area, outdoor space, correctional facility,industrial facility, or other environment. The networked lighting system100 provides variable illumination at higher efficiencies and lowercosts that conventional lighting systems. It can also be customized forenergy management, safety, and aesthetic appeal.

The networked lighting system 100 includes one or more lighting fixtures110, each of which includes one or more light sources, such aslight-emitting diodes (LEDs), fluorescent bulbs, etc. Each lightingfixture 110 is powered by switched alternating current (AC) power 142from a line voltage relay 140. As understood by those of ordinary skillin the art, the line voltage relay 140 contains at least one switch (notshown) that can be opened and closed to turn the switched AC power 142off and on, respectively.

Each lighting fixture 110 is also operably coupled to a respectivewireless network adapter 150 via a radio-frequency cable, an fiber opticlink, a wireless infrared link, or a radio-frequency wireless link(e.g., a ZigBee link). In some cases, a single wireless network adapter150 may be coupled to more than one lighting fixture 110; in othercases, the networked lighting system 100 include one (dedicated)wireless network adapter 150 for each lighting fixture 110.

The wireless network adapter 150 is powered by an AC power input 102(e.g., 100-277 VAC, 50/60 Hz) and coupled to an ambient light sensor 120and a low-voltage occupancy sensor 130 via wired or wireless links. Thewireless network adapter 150 includes one or more transformers thattransform the AC input power 102 into direct current (DC) power suitablefor powering the ambient light sensor 120 and the occupancy sensor 130.In this case, the wireless network adapter 150 supplies 24 VDC power 156to both the ambient light sensor 120 and the occupancy sensor 130.

The ambient light sensor 120 monitors the ambient light level in theenvironment illuminated by the lighting fixture 110 and provides a 0-10VDC analog ambient light level signal 122 representative of the amountof light that it detects. Similarly, the occupancy sensor 130 monitorsthe occupancy of the environment illuminated by the lighting fixture 110and provides a digital occupancy signal 132 (e.g., a 5 Vtransistor-transistor logic signal) representative of whether or not theenvironment is occupied.

The wireless network adapter 150 receives the ambient light level signal122 and the occupancy signal 132 from the ambient light sensor 120 andthe occupancy sensor 130, respectively, and processes them according toone or more rules stored in a memory (not shown). These rules govern thenetworked lighting system's response to changes in the ambient lightlevel, occupancy, time of day, day of the week, ambient temperature,lighting fixture temperature, energy consumption, and/or otherparameters that characterize the illuminated environment. A processor(not shown) in the wireless network adapter 150 implements a statemachine that evaluates changes in the lighting fixture's output based onthe sensor signals and the rules. For instance, if the wireless networkadapter 150 receives an ambient light level signal 122 that indicates anincrease in ambient light level and senses that the lighting fixture 110is operating at 70% of its maximum rated output, the wireless networkadapter 150 may reduce the lighting fixture's output to 60% of itsmaximum rated output. If the wireless network adapter 150 receives a“high” occupancy signal 132 after hours and senses that there is noappreciable ambient light and that the lighting fixture 110 is off, itmay turn the lighting fixture 110 to operate at 25% of its maximum ratedoutput.

The wireless network adapter 150 controls the lighting fixture 110 byadjusting an analog 0-10 VDC dimming signal 152 that determines thelighting fixture's output illumination level. Assuming no hysteresis orresponse nonlinearity, the lighting fixture's output illumination levelvaries linearly with the amplitude of the dimming signal: 10 VDCproduces the maximum illumination, 9 VDC produces 90% of the maximumillumination, and so on. Because the dimming signal 152 is an analogsignal, it must be supplied continuously for as long as the lightingfixture 110 is supposed to emit light at the desired output level. Inaddition, different fixtures respond differently to the same analogdimming signal, which makes it difficult to standardize control hardwarelike the wireless network adapter 150. Even a given fixture may responddifferently to the same analog dimming signal under differentenvironmental conditions (e.g., temperature) and at different points init useful life. To compensate for these variations, the wireless networkadapter 150 may have to be calibrated (and periodically recalibrated) tothe fixture 110, which can be time consuming and expensive.

The wireless network adapter 150 can also turn the entire lightingfixture 110 on and off. As shown in FIG. 1, the wireless network adapter150 supplies a digital relay output 154 to the line voltage relay 140that supplies switched AC power 142 to the lighting fixture 110. If thewireless network adapter 150 determines that there is no reason toilluminate the environment (e.g., there is no occupancy and theilluminated facility is closed), it can turn off the switched AC power142 by transmitting a digital relay output 154 that causes the switch inthe line voltage relay to open. This reduces the lighting fixture'spower consumption to zero; not even standby power is applied to thelighting fixture. It also gives the wireless network adapter 150 coarsecontrol of the lighting fixture's power consumption.

Digital Control Ready (DCR) Intelligent Lighting Systems

FIG. 2A shows an intelligent lighting system 200 that uses a two-wayopen standard for controlling and managing next-generation fixturesknown as the Digital Control Ready (DCR) standard. The DCR standard is asimple, extensible, and low-cost way to add energy-efficient andfeature-rich functionality to any lighting fixture or lighting system(e.g., lighting system 200). Compared to other networked lightingsystems, which may have many specialized, expensive components, the DCRintelligent lighting system 200 shown in FIG. 2A may be simpler and lessexpensive to install and operate. It may also be more easily expandedand more flexible than other networked lighting systems.

Using the DCR standard, a “dumb” DCR lighting fixture 210 can betransformed into an intelligent fixture capable of occupancy detection,daylight harvesting, task tuning, 0-100% digital dimming, and wirelesscontrol and management via a separate wireless digital lighting agent(DLA) 220. The DLA 220 connects to a gateway, server, or other centralmanagement device (not shown) via a network interface, such as anantenna, free-space optical transceiver, wired connection, or fiberoptic link. Because the DLA 220 is separate from the DCR lightingfixture 210, its antenna can be positioned to send and receive signalsover a longer range, with better signal fidelity, and/or with lowertransmit powers. In addition, the DLA's network interface (antenna)enables remote control of the DCR lighting fixture 210, e.g., using aninterface accessible from a networked device like a computer orsmartphone.

The DCR lighting fixture 210 is network-agnostic at the control layerand communicates using a bi-directional digital data link instead of a0-10 VDC analog dimming input. The DCR lighting fixture 210 is also“energy-aware”: it meters and reports its power and energy consumptionvia the data link. And it provides DC power (e.g., 24 VDC power from aclass 2 output) to power modular control accessories, including the DLA220.

In the intelligent lighting system 200 shown in FIG. 2A, the DCRlighting fixture 210 is coupled to the DLA 220 via a DCR cable 230,which includes a power wire 232, a common (ground) wire 234, and abidirectional data interface 236. The DCR lighting fixture 210 providesDC power to the DLA 220 via the power wire 232 and the common wire 234at a voltage 60 VDC, 40 VDC, 24 VDC, 12 VDC, 9 VDC, 5 VDC, or any othersuitable voltage. The DCR lighting fixture 210 generates this DC powerusing one or more transformers (not shown) to transform AC power from anAC input line 202 into DC power.

The DCR lighting fixture 210 exchanges information with the DLA 220 viathe bidirectional data interface 236, which may include one or morewires in the cable. In some cases, the data interface 236 may include asingle wire that supports time-multiplexed communication between the DCRlighting fixture 210 and the DLA 220. The data interface 236 may alsoinclude one or more wires that carry signals from the DCR lightingfixture 210 to the DLA 220 and one or more wires that carry signals fromthe DLA 220 to the DCR lighting fixture 210.

As understood by those of skill in the art, the power wire 232, thecommon wire 234, and the bidirectional data link 236 may each include aconductive wire (e.g., a solid or multi-strand metal wire) surround by acoaxial insulating layer, such as a concentric piece of solid plastic orrubber. If desired, the wires may also be at least partially encased byseparate metal shields or a common metal shield and an outer protectivelayer. Suitable physical standards for producing DCR cables 230 include,but are not limited to the local interconnect network (LIN) standard,the controller area network (CAN) standard, the KNX standard, and thedigital addressable lighting interface (DALI) standard. For example, theDCR cable 230 may conform to a suitable common standard, such as theRJ-45 standard, and be terminated with suitable connectors, such asRJ-45 connectors, RJ-11 connectors, terminal blocks, or any othersuitable type of connector.

Like other networked lighting systems, the intelligent lighting system200 shown in FIG. 2A is suitable for illuminating a warehouse,cold-storage facility, office space, retail space, sports venue, school,residential area, outdoor space, correctional facility, industrialfacility, or other environment. In operation, one or more light sources(e.g., LEDs) in the DCR lighting fixture 210 provide variableillumination according to digital control signals from the DLA 220.Because the DCR lighting fixture 210 responds to digital control signalsrather than analog control signals, it produces light with moreuniformly and more consistently than conventional (analog) fixtures.Light output also varies less from fixture to fixture for a givendigital control signal. The use of digital signaling also eliminates theneed for separate digital-to-analog adapters.

Unlike conventional fixtures, the DCR lighting fixture 210 measures itspower consumption, energy consumption (e.g., over a given period),operating temperature, commanded light level, actual light level,command color temperature, actual color temperature, color(chromaticity), output spectrum, remaining LED lifetime, etc., andreports these measurements to the DLA 220 on a periodic, as-needed, oras-commanded basis. This bidirectional communication can be used toimplement closed-loop feedback control for more precise lighting.

The DCR lighting fixture 210 may also report identifying information tothe DLA 220 (and/or to a fixture adapter as discussed below) via thebidirectional digital link 236. For instance, the DCR lighting fixture210 may transmit its serial number, model number, make, network address,physical location, or any other identification information to the DLA220, e.g., in response to a query from DLA 220, upon being powered up,on a periodic basis, or on any other suitable basis or timeline. The DCRlighting fixture 210 may also transmit information about itsconfiguration or capabilities, including but not limited to its maximumand minimum light output levels; its maximum and minimum rated powerconsumption; its color temperature and color temperature range; thenumber and orientation of the lighting modules in the lighting fixture;and the number, type, and expected lifetime of the light sources (e.g.,LEDs) in the lighting modules. Again, the DCR lighting fixture 210 maytransmit this information to the DLA 220 in response to a query from DLA220, upon being powered up, on a periodic basis, as part of a periodic“health check” broadcast, or on any other suitable basis or timeline

The DLA 220 receives and processes the measurements from the DCRlighting fixture 210. It also monitors the illuminated environment forchanges in occupancy, ambient light level, temperature, etc. with one ormore occupancy, ambient light level, and temperature sensors. The DLA220 may also receive commands and/or data from other sources, includinga central controller, other DLAs, and other DCR lighting fixtures, via anetwork interface, such as an antenna. The DLA 220 evaluates thisinformation according to one or more rules stored in memory (not shown).Each of these rules govern a transition between a pair of theintelligent lighting network's (or DCR lighting fixture's) possibleoperating states. For a given current operating state, there may afinite number of possible next operating states, with the transitionfrom the current operating state to a particular next operating statedetermined by a change in the environmental conditions and/or the DCRlighting fixture's operating parameters.

If the DLA 220 determines that the DCR lighting fixture's operatingstate should change (e.g., its light output should go down because it isconsuming too much power), it transmits a digital control signal to theDCR lighting fixture 210 that represents the DCR lighting fixture's newoperating state. This digital control signal may include bits (e.g., 4,8, 16, 32, or 64 bits) representing the DCR lighting fixture's light(dimming) level, color temperature, color, output spectrum, target powerconsumption, maximum power consumption, or any other fixture parameter.The DCR lighting fixture 210 adjusts its operating state in response tothis digital control signal, e.g., to a different light output level orcolor temperature. Because the command signal is digital, not analog, itdoes not have to be transmitted continuously—a single transmission isenough.

The DLA 220 may also reprogram the DCR lighting fixture 210 via thebidirectional data link 236. For instance, the DLA 220 may updatefirmware used by the DCR lighting fixture 220. It may also loadcalibration data or look-up table data used by the DCR lighting fixture210 to convert the digital command signals from the DLA 220 into voltageand/or current settings for driving the various components and modulesin the DCR lighting fixture 210, such as LED drivers for LEDs thatprovide the illumination. In addition, the DLA 220 may set one or moreof the DCR lighting fixture's “persistent” operating parameters, such asmaximum power or illumination levels.

Controlling Multiple DCR Lighting Fixtures

FIG. 2B illustrates a DCR-enabled networked lighting system 250 thatincludes several DCR lighting fixtures 210′, 210″, 210′″, and 210″″(collectively, fixtures 210) controlled by a single DLA 220. The DLA 220is connected to the first DCR lighting fixture 210′ via a first DCRcable 230′, just as in the system 200 shown in FIG. 2A. The secondfixture 210″ is connected to the first fixture 210′ via a second DCRcable 230″ or other suitable bi-directional data link, the third fixture210′″ is connected to the second fixture 210″ via a third DCR cable230′″, and so on. In other words, the fixtures 210 are daisy-chained tothe DLA 220 using respective DCR cables 230′, 230″, 230′″, 230″″(collectively, DCR cables 230).

As discussed above, the first DCR cable 230′ carries DC power as well asdata from the first fixture 210′ to the DLA 220. This data may includedata passed on from the other fixtures 210 in the daisy chain, includinginformation about the fixtures' current operating states, respectivepower consumption, and network health. This information may be passed upthe daisy chain, e.g., from the third fixture 210′″ to the secondfixture 210″ and so on, with each successive fixture 210 simply routingthe information rather than analyzing or processing it in any way. Theupstream data may be addressed or marked with header information thatsignifies its origin (e.g., the third fixture 210′″).

The first DCR cable 230′ also carries digital control signals from theDLA 220 to the first fixture 210′, which acts on commands that affectits operating state and transmits commands addressed to other fixtures210 down the daisy chain via the other cables 230. These digital controlsignals may include broadcast messages that affect every fixtures 210 inthe network 250 (e.g., “power off” or “increase light output”) as wellas messages targeted to a particular fixture 210 or group of fixtures210. These fixture-specific messages may be based on localizedenvironmental changes, such as detected activity (motion), predictedmotion, or changes in ambient light levels (e.g., more light comingthrough a particular window or skylight) in a particular section of theilluminated environment. The second and subsequent cables 230 may or maynot carry DC power between the fixtures 230 depending on the fixtures'particular power requirements and available power supplies.

Digital Control Ready (DCR) Lighting Fixtures

FIG. 3 is a block diagram of the DCR lighting fixture 210 shown in FIG.2A. The DCR lighting fixture 210 includes a power meter 310, alow-voltage power supply 320, a processor (microcontroller 330), one ormore LED drivers 340, and a DCR interface (port) 350. It also includesone or more LED modules 342 a, 342 b, . . . , 342 n (collectively, LEDmodules 342), each of which includes one or more LEDs. The LED modules342 consume power and emit light according to digital control signalsreceived by the microcontroller 330 from the DLA 220 (FIG. 2A) via theDCR port 350, which may conform to the RJ-45 standard. In some cases,the DCR lighting fixture 210 may have additional DCR ports 350, e.g., tosupport daisy-chain connections as shown in FIG. 2B or to supportconnection to other DCR-enabled devices.

The power meter 310 is coupled to an AC input 302 that receives line ACpower from an external source. The power meter 310 may be implemented inhardware or software and measures the power consumed by the DCR lightingfixture 100. By way of non-limiting example, the power meter 310 mayinclude a Cirrus CS5490 two-channel energy measurement integratedcircuit that provides high-accuracy energy measurement, on-chip energycalculations, and fast on-chip calibration. It may also count orintegrate the amount of energy consumed by the DCR lighting fixture 100over a given period (e.g., over the most recent billing interval orsince the last query or report). Some examples of the power meter 310may also track how much power is consumed by each component or module inthe fixture 210. For instance, the power meter 310 may measure how muchpower (and energy) is consumed by the low-voltage supply 320, themicrocontroller 330, and the LED driver(s) 340.

The power meter 310 supplies the power consumption data and the energyconsumption data to the microcontroller 330, which reports the data tothe DLA 220 (FIG. 2A) via the DCR port 350, which includes a +DC port352, a data input port 354, a data output port 356, and a ground port358. The microcontroller 330 also reports other data about the fixture'soperating state, such as its operating temperature, the colortemperature of the LEDs, the actual LED output (which may be measuredwith a photosensor coupled to the microcontroller 330), and indicationsof malfunctions (e.g., error messages). It reports this information bygenerating and transmitting one or more digital signals to the DLA 220(not shown) via a data output port 356 in the DCR port 350. Themicrocontroller 330 may report some or all of this data to the DLA 220at regular intervals (e.g., every hour), when commanded to by the DLA220, in response to predetermined events (e.g., at power-up, power-off,or in the event of a component failure).

The microcontroller 330 also receives, processes, and carries outdigital control signals from the DLA 220. For instance, if themicrocontroller 330 receives a digital control signal indicating adesired change in the light level or color temperature provided by theLED modules 342, it actuates the LED driver(s) 340 so as to provide thedesired light level. The LED driver(s) 340 respond(s) to this actuationby increasing or decreasing the current provided to the LED modules 342,which in turn causes the light level to increase or decrease,respectively. The microcontroller 330 may also actuate the LED driver(s)340 so as to actuate the color temperature, color, beam angle, number ofbeams, beam footprint(s), etc. of the beams of light emitted by the LEDmodules 342.

As mentioned above, the DCR lighting fixture 210 also provides DC powerto the DLA 220 via a +DC port 352 in the DCR interface 350. This poweris generated by the low-voltage power supply 320, which receives ACpower from the AC input 302 via the power meter 310. The low-voltagepower supply 320 includes at least one AC-DC converter to transform theAC power into DC power suitable for powering the DLA 220, themicrocontroller 330, the LED driver(s) 340, and the other electroniccomponents in the DCR lighting fixture 210. The low-voltage power supply320 may also include one or more DC-DC converters to step up or down theDC voltage from the AC-DC converter as desired.

DCR Digital Light Agents

FIG. 4 is a schematic diagram of the digital light agent (DLA) 220 shownin FIG. 2A. Embodiments of the DLA 220 can be made from low-cost,commodity hardware and feature compact and flexible designs for easyinstallation. For instance, the DLA 220 may have electrical andmechanical connections that make it possible to upgrade an existingfixture in a matter of minutes. Once installed, the DLA 220 providesintelligent occupancy control, task tuning, and daylight harvesting forreduced power consumption.

The DLA 220 includes a processor (microcontroller 410), a DC powerconverter 420, a electrically erasable programmable read-only memory(EEPROM) 430, a networking module 440, a DCR interface 450, and anextensible sensor bus 460 that holds one or more integrated sensors 462a, 462 b, . . . , 462 n (collectively, sensors 462) disposed within ahousing 470. As understood by those of ordinary skill in the art, theseelectronic components may be operably coupled together via electricalconnections (conductive traces) or optical connections (free-space orwaveguide links).

The DCR interface 450 is configured to receive DC power and data and totransmit data to a DCR lighting fixture 210 (FIG. 2A) or otherDCR-compatible component via a DCR cable 230. As described above, theDCR port includes a DC voltage port (e.g., +12 VDC to +24 VDC), a commonport, and one or more data ports. Power received via the DCR port 450flows to the DC power converter 420, which steps up or down the receivedDC voltage to voltage levels suitable for powering the microcontroller410, memory 430, sensors 462, and other electronic components in the DLA220.

The sensors 462 may include but are not limited to an occupancy sensor462 a (e.g., a dual-element passive infrared occupancy sensor), adigital ambient light sensor 462 b, an internal temperature sensor, anexternal temperature sensor, a real-time clock, and a power meter (e.g.,a utility-grade power meter). These sensors 462 detect environmentalconditions associated with the environment illuminated by the fixture210 and/or the network 200 and conditions of the DLA 220 itself. Ifdesired, one or more of the sensors 462 may be optically coupled torespective lenses for improved sensing capabilities. These lenses may bechosen based on the DLA's position within the illuminated environment.For instance, the lenses may provide wide-area coverage for high-bay andoutdoor mounting, narrower coverage for mid-bay mounting, etc.

The sensors 462, including the occupancy sensor 462 a and the ambientlight sensor 462 b, can be calibrated so as to adapt the lightingnetwork's performance to specific characteristics of the environment.For instance, the occupancy sensor 462 a may be calibrated so as toprovide different degrees of responsiveness for people and vehicles.Similarly, the ambient light sensor 462 b may be calibrated to accountor compensate for variations in reflectivity of surfaces in theenvironment, the presence of obstructions between the sensor 462 b andwindows or skylights, etc. The DLA 220 may carry out one or more ofthese calibrations internally, e.g., based on information about thesensor 462 (e.g., sensor element, lens, amplifier, etc.) derived by orprovided to the microcontroller 410. The DLA 220 may also be calibratedmanually or via external command based on sensor measurements of knownstimuli (e.g., known ambient light levels or known occupancy profiles).Sensor calibration can be automated and/or continuous (e.g., asimplemented with open-loop feedback derived from sensor data). It canalso be carried discretely (e.g., during installation or routinemaintenance) using handheld calibration tools, software, push-buttoninterfaces on the DLA 220, etc.

The DLA 220 may also use data from the ambient light sensor 462 b toperform aging/depreciation compensation of the DCR lighting fixture'sLEDs. To do this, the DLA 220 tracks the relationship between thecommanded light level and the detected light level over time, possiblyby storing records (data) about the commanded and detected light levelsin the EEPROM 430. The DLA 220 either analyzes this data itself ortransmits the data via the networking module 440 to an externalprocessor or management module for analysis. In either case, theanalysis involves determining changes in the detected light level for agiven commanded light level. In other words, the DLA 220 or externalprocessor determines how much light the DCR lighting fixture 210 shouldbe generating, and how much it actually is generating, and adjusts thecalibration constants in the DCR lighting fixture 210 accordingly.Lighting level changes on short time scales (e.g., minutes, hours, ordays) may indicate environmental changes, whereas more gradual changesmay indicate LED degradation, sensor degradation, or both. Abruptchanges in the detected light level for a given commanded light levelmay represent either environmental changes or component failures. Insome cases, these changes can be disambiguated with data from othersensors (e.g., the occupancy sensor 462 a), components, or user input.

The microcontroller 410 may log sensor data and fault information fromthe DLA's electronic components and the lighting fixture 210 (FIG. 2A)in the memory 430. For instance, the microcontroller 410 may logoccupancy data as a function of time for later analysis of occupancy andtraffic patterns in the illuminated environment. It may also log andanalyze longer-term changes, such as changes in average ambient lightlevel with the time of year. This data may be analyzed, either on-boardthe DLA 220 or remotely, to adjust operation of the lighting system 200,e.g., so as to reduce power consumption, improve safety, etc.

The microcontroller 410 may also use real-time and logged sensor tocontrol the DCR fixture 210 so as to provide light only when and whereit is needed, dramatically reducing lighting-related energy usage. Forinstance, the occupancy sensor 462 a may provide, to the microcontroller410, a multi-bit digital signal that represents the number of occupants,the types of occupant (e.g., vehicles or people), and the occupants'trajectories (e.g., no movement, straight-line movement, etc.) in theenvironment illuminated by the lighting system 200. The microcontroller410 responds to this multi-bit signal by generating one or more digitalcontrol signals according to rules stored in the memory and transmitsthe digital control signal(s) to the DCR lighting fixture 210 (FIG. 2A)via the DCR port 450 (e.g., an RJ-45 port).

Similarly, the microcontroller 410 may command the DCR lighting fixture210 to change state based on changes in the ambient light level detectedby the digital ambient light sensor 462 b. In some cases, the DLA 220may implement “daylight harvesting” by reducing the amount of lightprovided by the fixture 210 when the ambient light level increases. Inother words, the DLA 220 may automatically dim the light fixture 210when the amount of sunlight (or light from other sources) increases soas to maintain a constant light level in the environment illuminated bythe lighting system 200. This real-time feedback allows for precisecontrol of delivered light in dynamic conditions.

The DLA 220 may also generate digital command signals that providelighting that is tuned to a particular task undertaken by an occupant ofthe illuminated environment. This type of lighting control andmanagement, which is known as “task tuning,” involves using the ambientlight sensor 462 b embedded in the DLA 220 to allow a user to customizedelivered light levels to the specific task at hand. Because most spaces(environments) are overlit by design, this typically results insubstantial savings. For example, the user may set the desired lightlevel (e.g., 30 ft-cd) at a particular task height (e.g., rack height)or task surface (e.g., the surface of a desk) using an interface (e.g.,a web browser or smartphone app) that is communicatively coupled to theDLA 220. The DLA 220 responds to this instruction by adjusting theillumination provided by the DCR fixture 210 to provide the desiredlight level using closed-loop feedback provided by ambient light levelmeasurements from the ambient light sensor 462 b. In some cases the DLA220 may employ a calibrated transfer function to map the measuredambient light level(s) to the light level at the task height asdisclosed in PCT/US2012/63372, filed Nov. 2, 2012, and entitled“METHODS, APPARATUS AND SYSTEMS FOR INTELLIGENT LIGHTING,” which isincorporated herein by reference in its entirety.

Daylight harvesting, occupancy-based lighting, and other task- andenvironmental-based lighting behavior can be controlled and adjusteddynamically using instructions (software) stored in the memory 430coupled to the microcontroller 410. For example, these instructions maycause the microcontroller 410 to implement a state machine based onrules governing the system's response to changing environmental andsystem parameters. They may also cause changes in illumination based ona schedule provided by a facility user or operator. The instructionsstored in the memory 430 may be augmented, updated, or overwritten withinstructions from a server, gateway, or other central management modulecommunicatively coupled to the DLA 220 via the networking module 440. Inaddition, the networking module 440 may receive instructions forreal-time control of the lighting fixture 210, the DLA 220, and/or anyother part of the lighting system 200. The networking module 440 mayalso serve as a node in a wireless mesh network or multi-hop wirelessnetwork.

As understood by those of ordinary skill in the art, the networkingmodule 440 may include a radio-frequency (rf) antenna (not shown) forwireless communication with a ZigBee/IEEE 802.15.4 link, Wi-Fi router,wireless gateway, or other suitable wireless device. In some cases, theantenna is disposed within the housing 470, which can be thin andpermeable enough at rf wavelengths not to impede wireless communication.In other cases, at least part of the antenna protrudes through thehousing 470 to prevent undesired attenuation or interference withsignals transmitted and received by the antenna.

The networking module 440 may also be used to commission the DLA 220after installation. For instance, the DLA 220 may be configuredwirelessly using a cross-platform (Win/Mac) commissioning toolapplication (not shown) coupled with a USB ZigBee radio. This wirelesstoolkit allows installers and/or end users to: assign a name or addressto the fixture for identification purposes; set the active and inactivelight levels; set a timeout for the occupancy sensor 462 a; and setambient light targets for active and inactive states. If desired, theuser can calibrate the ambient light sensor 462 b use the commissioningtool application and a separate (e.g., handheld) light meter orphotodetector. This calibration may be used to fine-tune or augment theDLA's factory calibration, which may encompass using software andhardware to calibrate the DLA's software-based power estimator. The usermay also use the commissioning tool application to download logged data,including event history and energy usage, and update the firmware storedin the memory 430.

As mentioned above, the DLA's electronic components may be disposedwithin a housing 470 The housing's physical form factor may be based onPCA spatial requirements, sensor lens constraints, and desired wirelessantenna coverage. For example, the housing 470 may be shaped for surfacemounting, mounting in a recessed junction box enclosure, or mounting ona conduit to a lighting fixture 210. In one embodiment, it is about 11cm high by 11 cm wide by 3.0 cm in deep. It may be injection-molded orotherwise formed from a polymeric material, such as acrylonitrilebutadiene styrene (ABS) polymer, that is tough, resistant to impact andheat, and conforms with the appropriate fire and electrical safetystandards. The housing 470 may protect the DLA's electronic componentswell enough to sustain operation over a temperature range of about −40°C. to about 50° C. and a humidity range of about 0% to about 95%.

DCR Intelligent Lighting Systems with Conventional Lighting Fixtures

FIG. 5A is a diagram of a DCR networked lighting system 500 thatincludes a conventional dimmable lighting fixture 110 (described abovewith respect to FIG. 1). The conventional fixture 110 is operablycoupled to a DLA 220 via a DCR digital light agent fixture adapter(DLAFA) 520. The DLA 220 is connected to the fixture adapter 520 via aDCR cable 230, and the DLAFA is operably connected to the conventionalfixture 110.

As shown in FIG. 5A, the fixture adapter 520 transforms the conventionalfixture 110 into a DCR fixture from the perspective of the DLA 220. Thefixture adapter 520 transforms AC power from an AC input 502 into DCpower (e.g., at +60, +40, +24, +12, +9, or +5 VDC), which it supplies tothe DLA 220. The fixture adapter 520 also supplies switched AC power tothe conventional fixture 110 via an AC line 522 connecting the fixtureadapter 520 to the fixture 110.

In addition, to supplying power, the fixture adapter 520 monitors thefixture's power consumption, energy consumption, etc. It reports thisdata to the DLA 220 via the DCR cable 230 as described above withrespect to FIG. 2A. The fixture adapter 520 also receives digitalcontrol signals from the DLA 220 and uses them to generate 0-10 VDCanalog dimming signals suitable for controlling the intensity of thelight emitted by the lighting fixture 110.

Like the DLA 220 shown in FIG. 2B, a DLAFA can used to control more thanone conventional lighting fixture 110 at a time. For instance, FIG. 5Billustrates a networked lighting system 550 that includes severalconventional lighting fixtures 110′, 110″, and 110′″ (collectively,fixtures 110) controlled by a single DLA 220 via a single fixtureadapter 520. In this particular configuration (i.e., one DLA 220connected to one fixture adapter 520, which is connected in turn to manyconventional fixtures 110), the fixture adapter 520 provides a singleanalog dimming signal that causes all of the connected fixtures 110 todim simultaneously to the same dimming/light level. The fixture adapter520 provides the analog dimming signal and switched AC power to thefirst lighting fixture 110′ via a first power line 522′ and a firstanalog control line 524′, just as in the system 500 shown in FIG. 5A.The second fixture 110″ is connected to the first fixture 110′ via asecond power line 522″ and a second analog control line 524″, and so on.In other words, the fixtures 110 are daisy-chained to the fixtureadapter 520 using respective AC power lines 522′, 522″, and 522″(collectively, AC power lines 522) and respective analog control lines524′, 524″, and 524″ (collectively, analog control lines 524).

DCR Digital Light Agent Fixture Adapter (DLAFA)

FIG. 6 is a block diagram of the fixture adapter 520 used in thenetworked lighting systems 500 and 550 of FIGS. 5A and 5B, respectively.The fixture adapter 520 includes a power meter 610, a low-voltage powersupply 620, a processor (microcontroller 630), a signal conditioningblock 640, at least one DCR port 650 (e.g., two DCR ports 650), and aswitchable AC relay 660 all disposed within a housing 670. The powermeter 610 is coupled to the AC input 502 and provides utility-gradepower metering for turning lights into managed energy resources. Itmeasures and records the amount of power consumed by the fixture adapter520 and the amount of switched AC power provided to the lightingfixtures 110 via a switched AC power output 662, which may comprise ACline, neutral, ground, and switched connections. It also provides ACpower to the switchable AC relay 660 and to the low-voltage power supply620, which transforms the AC power into DC power (e.g., about +12 VDC toabout +24 VDC) for powering the DLA 220 via the DCR port 650.

The DCR port 650, which may be an RJ-45 compatible connector, alsotransmits data to connected DCR-compatible control modules like the DLA220. The transmitted data includes power consumption information fromthe power meter 610, as well as possibly information about the health ofthe fixture 110, the fixture adapter 520, and the network. For instance,the fixture adapter 520 may report faults in its own circuitry to theDLA 220.

The DCR port 650 also enables the fixture adapter 520 to providefull-range (e.g., 0-10 VDC) dimming control for adding smooth digitaldimming to a wide range of legacy fixture types. As described above, theDLA 220 generates digital control signals for changing the light level,color temperature, chromaticity, etc. of the illumination emitted by thefixture 110 based on data from the fixture adapter 520. In this case,the fixture adapter 520 receives these digital control signals andconverts them to 0-10 V analog dimming signals using signal conditioningcircuitry 640. This signal conditioning circuitry 640 transmits theanalog dimming signals to the fixture via a dimming output 642, whichmay include a 0-10 VDC output connector and a 0-10 VDC referenceconnector. The fixture adapter 520 may supply this analog dimming signalcontinuously until it receives another digital control signal from theDLA 220. As mentioned above, one of the problems with 0-10 VDC dimmingcontrol is that it is not guaranteed to be consistent from fixture tofixture—for example, two otherwise identical fixtures may outputdifferent light levels when both are dimmed to 3.5 V on the 0-10 VDCinput. Because of this, the fixture adapter 520 may also store andexecute a programmable calibration function to allow customization ofthe relationship between commanded output level (e.g. “set to 35% ofmaximum brightness” coming from the DLA 220) and the 0-10 VDC outputsignal.

Like the DCR lighting fixture 210, the fixture adapter 520 may transmitidentifying information, such as type and serial number, and capabilityinformation, such as a maximum light output and color temperature, tothe DLA 220. It may do this in response to a query from the DLA 220, aspart of a periodic “health-check” transmission, upon power up, etc. Thefixture adapter 520 may derive and/or store information about theconventional fixture 110, such as fixture type, location, capability,etc., and provide this information to DLA 220, either automatically orin response to a command.

In addition, the DLA 220 may also reprogram the fixture adapter 520 viathe bidirectional data link 236. For instance, the DLA 220 may updatefirmware used by the fixture adapter 520. It may also load calibrationdata or look-up table data used by the DCR lighting fixture 220 toconvert the digital command signals from the DLA 220 into analog dimmingsignal voltage levels for controlling the fixture 110. In addition, theDLA 220 may set one or more of the fixture adapter's “persistent”operating parameters, such as maximum power or illumination levels.

The fixture adapter 520 may include a housing 670 that defines acompact, bolt-on enclosure, e.g., one with a rugged, small form factorIP30-rated ABS enclosure suitable for mounting in a variety ofenvironments. For instance, the housing 670 may be about 2.5 cm high by3.0 cm wide by 17.8 cm deep. It may be injection-molded or otherwiseformed from a polymeric material, such as ABS polymer, that is tough,resistant to impact and heat, and conforms with the appropriate fire andelectrical safety standards. The housing 670 may protect the fixtureadapter's electronic components well enough to sustain operation over atemperature range of about −40° C. to about 50° C. and a humidity rangeof about 0% to about 95%.

Energy Savings

FIGS. 7A-7D and 8 illustrate energy savings achievable with a DCRintelligent lighting system such as the ones shown in FIGS. 2A, 2B, 5A,and 5B. The plots in FIGS. 7A-7D show power consumption versus time ofday for different types of behavior management supported by a DCRintelligent lighting system and the (constant) power consumption of afixture that is always on (or turned on at the start of the work day(e.g., 6 am) and turned off at the end of the work day (e.g., 6 pm)).The highlighted areas represent the reduction in energy consumptionrealized with the corresponding behavior control as compared to theenergy consumption of a comparable lighting system that is always on.FIG. 7A shows that multi-level occupancy-based control results in a20-80% energy savings; FIG. 7B shows that task tuning results in a 5-40%energy savings; FIG. 7C shows that daylight harvesting results in up 30%energy savings; and FIG. 7D shows that scheduling results in a 5-30%energy savings. FIG. 8 shows energy savings apportioned to each type ofbehavior management. These plots show that using many different types ofsensors (occupancy, ambient light, time-of-day) and control strategies(e.g., multi-level occupancy-based control, task-tuning, daylightharvesting, and scheduling) leads to greater energy savings. Oneinnovation associated with the DCR lighting networks and DCR-enabledlighting fixtures, fixture adapters, and DLAs disclosed herein is theintegration of these different types of sensors into a low-cost, modularhardware package (e.g., DLA 220 in FIG. 2) and using software toimplement the control strategies (versus the hard-wired behavior of themulti-box architecture shown in FIG. 1).

CONCLUSION

While various inventive embodiments have been described and illustratedherein, those of ordinary skill in the art will readily envision avariety of other means and/or structures for performing the functionand/or obtaining the results and/or one or more of the advantagesdescribed herein, and each of such variations and/or modifications isdeemed to be within the scope of the inventive embodiments describedherein. More generally, those skilled in the art will readily appreciatethat all parameters, dimensions, materials, and configurations describedherein are meant to be exemplary and that the actual parameters,dimensions, materials, and/or configurations will depend upon thespecific application or applications for which the inventive teachingsis/are used. Those skilled in the art will recognize, or be able toascertain using no more than routine experimentation, many equivalentsto the specific inventive embodiments described herein. It is,therefore, to be understood that the foregoing embodiments are presentedby way of example only and that, within the scope of the appended claimsand equivalents thereto, inventive embodiments may be practicedotherwise than as specifically described and claimed. Inventiveembodiments of the present disclosure are directed to each individualfeature, system, article, material, kit, and/or method described herein.In addition, any combination of two or more such features, systems,articles, materials, kits, and/or methods, if such features, systems,articles, materials, kits, and/or methods are not mutually inconsistent,is included within the inventive scope of the present disclosure.

The above-described embodiments can be implemented in any of numerousways. For example, the embodiments may be implemented using hardware,software or a combination thereof. When implemented in software, thesoftware code can be executed on any suitable processor or collection ofprocessors, whether provided in a single computer or distributed amongmultiple computers.

Further, it should be appreciated that a computer may be embodied in anyof a number of forms, such as a rack-mounted computer, a desktopcomputer, a laptop computer, or a tablet computer. Additionally, acomputer may be embedded in a device not generally regarded as acomputer but with suitable processing capabilities, including a PersonalDigital Assistant (PDA), a smart phone or any other suitable portable orfixed electronic device.

Also, a computer may have one or more input and output devices. Thesedevices can be used, among other things, to present a user interface.Examples of output devices that can be used to provide a user interfaceinclude printers or display screens for visual presentation of outputand speakers or other sound generating devices for audible presentationof output. Examples of input devices that can be used for a userinterface include keyboards, and pointing devices, such as mice, touchpads, and digitizing tablets. As another example, a computer may receiveinput information through speech recognition or in other audible format.

Such computers may be interconnected by one or more networks in anysuitable form, including a local area network or a wide area network,such as an enterprise network, and intelligent network (IN) or theInternet. Such networks may be based on any suitable technology and mayoperate according to any suitable protocol and may include wirelessnetworks, wired networks or fiber optic networks.

The DLAs, DLAFAs, DCR lighting fixtures, and other electronic devicesdisclosed herein may each include a memory (e.g., EEPROM 430 in FIG. 4),one or more processing units (also referred to herein simply as“processors”; e.g., microcontrollers 310, 410, and 610), one or morecommunication interfaces (e.g., DCR ports 350, 450, and 650), one ormore display units (e.g., LEDs, liquid-crystal displays, etc.), and oneor more data input devices (e.g., keypads, antennas, etc.). The memorymay comprise any computer-readable media, and may store computerinstructions (also referred to herein as “processor-executableinstructions”) for implementing the various functionalities describedherein. The processing unit(s) may be used to execute the instructions.The communication interface(s) may be coupled to a wired or wirelessnetwork, bus, or other communication means and may therefore allow theelectronic device to transmit communications to and/or receivecommunications from other devices. The display unit(s) may be provided,for example, to allow a user to view various information in connectionwith execution of the instructions. The user input device(s) may beprovided, for example, to allow the user to make manual adjustments,make selections, enter data or various other information, and/orinteract in any of a variety of manners with the processor duringexecution of the instructions.

The various methods or processes outlined herein may be coded assoftware that is executable on one or more processors that employ anyone of a variety of operating systems or platforms. Additionally, suchsoftware may be written using any of a number of suitable programminglanguages and/or programming or scripting tools, and also may becompiled as executable machine language code or intermediate code thatis executed on a framework or virtual machine.

In this respect, various inventive concepts may be embodied as acomputer readable storage medium (or multiple computer readable storagemedia) (e.g., a computer memory, one or more floppy discs, compactdiscs, optical discs, magnetic tapes, flash memories, circuitconfigurations in Field Programmable Gate Arrays or other semiconductordevices, or other non-transitory medium or tangible computer storagemedium) encoded with one or more programs that, when executed on one ormore computers or other processors, perform methods that implement thevarious embodiments of the invention discussed above. The computerreadable medium or media can be transportable, such that the program orprograms stored thereon can be loaded onto one or more differentcomputers or other processors to implement various aspects of thepresent invention as discussed above.

The terms “program” or “software” are used herein in a generic sense torefer to any type of computer code or set of computer-executableinstructions that can be employed to program a computer or otherprocessor to implement various aspects of embodiments as discussedabove. Additionally, it should be appreciated that according to oneaspect, one or more computer programs that when executed perform methodsof the present invention need not reside on a single computer orprocessor, but may be distributed in a modular fashion amongst a numberof different computers or processors to implement various aspects of thepresent invention.

Computer-executable instructions may be in many forms, such as programmodules, executed by one or more computers or other devices. Generally,program modules include routines, programs, objects, components, datastructures, etc. that perform particular tasks or implement particularabstract data types. Typically the functionality of the program modulesmay be combined or distributed as desired in various embodiments.

Also, data structures may be stored in computer-readable media in anysuitable form. For simplicity of illustration, data structures may beshown to have fields that are related through location in the datastructure. Such relationships may likewise be achieved by assigningstorage for the fields with locations in a computer-readable medium thatconvey relationship between the fields. However, any suitable mechanismmay be used to establish a relationship between information in fields ofa data structure, including through the use of pointers, tags or othermechanisms that establish relationship between data elements.

Also, various inventive concepts may be embodied as one or more methods,of which an example has been provided. The acts performed as part of themethod may be ordered in any suitable way. Accordingly, embodiments maybe constructed in which acts are performed in an order different thanillustrated, which may include performing some acts simultaneously, eventhough shown as sequential acts in illustrative embodiments.

All definitions, as defined and used herein, should be understood tocontrol over dictionary definitions, definitions in documentsincorporated by reference, and/or ordinary meanings of the definedterms.

The indefinite articles “a” and “an,” as used herein in thespecification and in the claims, unless clearly indicated to thecontrary, should be understood to mean “at least one.”

The phrase “and/or,” as used herein in the specification and in theclaims, should be understood to mean “either or both” of the elements soconjoined, i.e., elements that are conjunctively present in some casesand disjunctively present in other cases. Multiple elements listed with“and/or” should be construed in the same fashion, i.e., “one or more” ofthe elements so conjoined. Other elements may optionally be presentother than the elements specifically identified by the “and/or” clause,whether related or unrelated to those elements specifically identified.Thus, as a non-limiting example, a reference to “A and/or B”, when usedin conjunction with open-ended language such as “comprising” can refer,in one embodiment, to A only (optionally including elements other thanB); in another embodiment, to B only (optionally including elementsother than A); in yet another embodiment, to both A and B (optionallyincluding other elements); etc.

As used herein in the specification and in the claims, “or” should beunderstood to have the same meaning as “and/or” as defined above. Forexample, when separating items in a list, “or” or “and/or” shall beinterpreted as being inclusive, i.e., the inclusion of at least one, butalso including more than one, of a number or list of elements, and,optionally, additional unlisted items. Only terms clearly indicated tothe contrary, such as “only one of” or “exactly one of,” or, when usedin the claims, “consisting of,” will refer to the inclusion of exactlyone element of a number or list of elements. In general, the term “or”as used herein shall only be interpreted as indicating exclusivealternatives (i.e. “one or the other but not both”) when preceded byterms of exclusivity, such as “either,” “one of,” “only one of,” or“exactly one of.” “Consisting essentially of,” when used in the claims,shall have its ordinary meaning as used in the field of patent law.

As used herein in the specification and in the claims, the phrase “atleast one,” in reference to a list of one or more elements, should beunderstood to mean at least one element selected from any one or more ofthe elements in the list of elements, but not necessarily including atleast one of each and every element specifically listed within the listof elements and not excluding any combinations of elements in the listof elements. This definition also allows that elements may optionally bepresent other than the elements specifically identified within the listof elements to which the phrase “at least one” refers, whether relatedor unrelated to those elements specifically identified. Thus, as anon-limiting example, “at least one of A and B” (or, equivalently, “atleast one of A or B,” or, equivalently “at least one of A and/or B”) canrefer, in one embodiment, to at least one, optionally including morethan one, A, with no B present (and optionally including elements otherthan B); in another embodiment, to at least one, optionally includingmore than one, B, with no A present (and optionally including elementsother than A); in yet another embodiment, to at least one, optionallyincluding more than one, A, and at least one, optionally including morethan one, B (and optionally including other elements); etc.

In the claims, as well as in the specification above, all transitionalphrases such as “comprising,” “including,” “carrying,” “having,”“containing,” “involving,” “holding,” “composed of,” and the like are tobe understood to be open-ended, i.e., to mean including but not limitedto. Only the transitional phrases “consisting of” and “consistingessentially of” shall be closed or semi-closed transitional phrases,respectively, as set forth in the United States Patent Office Manual ofPatent Examining Procedures, Section 2111.03.

What is claimed is:
 1. A system for providing variable illumination to an environment, the system comprising: (A) at least one digital control ready (DCR) lighting fixture, disposed in a first location of the environment, to provide the variable illumination to at least a portion of the environment, the at least one DCR lighting fixture comprising: (A1) a fixture housing; (A2) at least one light source, in mechanical association with the fixture housing, to generate the variable illumination in response to at least one digital control signal; (A3) at least one light source driver, in mechanical association with the fixture housing and operably coupled to the at least one light source, to power the at least one light source according to the at least one digital control signal; (A4) an alternating current (AC) power input, in mechanical association with the fixture housing and operably coupled to the at least one light source driver, to provide AC power to the at least one light source driver; (A5) a power converter, in mechanical association with the fixture housing and operably coupled to the AC power input, to convert the AC power to direct current (DC) power at a voltage of less than or equal to +60 V; (A6) a power meter, in mechanical association with the fixture housing and operably coupled to at least one of the at least one light source driver, the AC power input, and the power converter, to measure power consumption of the at least one DCR lighting fixture; and (A7) a fixture input/output bus, in mechanical association with the fixture housing and operably coupled to the at least one light source, the power converter, and the power meter, to receive the at least one digital control signal and to provide at least a portion of the DC power and at least one digital reporting signal representative of at least one of the power consumption and a light output of the at least one DCR lighting fixture; and (B) at least one digital light agent (DLA), disposed in a second location of the environment and operably coupled to the at least one DCR lighting fixture, to control the at least one DCR lighting fixture in response to at least one change in the environment, the at least one DLA comprising: (B1) a DLA housing; (B2) at least one sensor, in mechanical association with the DLA housing, to provide at least one sensor signal representative of the at least one change in the environment; (B3) a memory, in mechanical association with the DLA housing, to store at least one rule governing a change in the variable illumination provided by the at least one DCR lighting fixture based at least in part on the at least one change in the environment; (B4) a processor, in mechanical association with the DLA housing and operably coupled to the at least one sensor and to the memory, to generate the at least one digital control signal based on the at least one rule and the at least one sensor signal; and (B5) a DLA input/output bus, in mechanical association with the DLA housing and operably coupled to the processor, to receive the at least the portion of the DC power and the at least one digital reporting signal from the at least one DCR lighting fixture and to provide the at least one digital control signal to the at least one DCR lighting fixture; and (B6) a network interface, in mechanical association with the DLA housing and operably coupled to the processor, to provide data representative of at least one of the at least one digital reporting signal, the at least one digital control signal, and the at least one sensor signal to a user.
 2. The system of claim 1, wherein the at least one DCR lighting fixture further comprises: a first DCR lighting fixture operably coupled to the at least one DLA via a first cable; and a second DCR lighting fixture operably coupled to the at least one DLA via a second cable coupled to the first DCR lighting fixture.
 3. The system of claim 2, wherein the at least one DCR lighting fixture further comprises: a third DCR lighting fixture operably coupled to the at least one DLA via a third cable coupled to the second DCR lighting fixture.
 4. The system of claim 1, wherein the power converter provides the at least a portion of the DC power at a voltage that is less than or equal to +40 VDC.
 5. The system of claim 1, wherein the power converter provides the at least a portion of the DC power at a voltage that is about +12 VDC to about +24 VDC.
 6. The system of claim 1, wherein the at least one digital reporting signal comprises information representing at least one of the power consumption, energy consumption, AC power quality, color temperature, light intensity, and temperature associated with the at least one.
 7. The system of claim 1, wherein the fixture input/output bus and the DLA input/output bus each comprise: a respective power port for the second portion of the DC power; a respective common port for a reference voltage level; and at least one respective data port for the at least one digital reporting signal and the at least one digital control signal.
 8. The system of claim 1, wherein the fixture input/output bus and the DLA input/output bus are each compatible with at least one of a local interconnect network (LIN) standard, a controller area network (CAN) standard, a KNX standard, and a digital addressable lighting interface (DALI) standard.
 9. The system of claim 1, wherein the at least one sensor comprises at least one of an occupancy sensor, a temperature sensor, an ambient light level sensor, and a clock.
 10. The system of claim 1, wherein the network interface is configured to communicate via a wireless link.
 11. The system of claim 1, further comprising: (C) at least one cable connecting the fixture input/output bus to the DLA input/output bus.
 12. The system of claim 11, wherein the at least one cable comprises at least one of a local interconnect network (LIN) cable, a controller area network (CAN) cable, a KNX cable, and a digital addressable lighting interface (DALI) cable.
 13. The system of claim 1, wherein the at least one light source comprises at least one light-emitting diode (LED) and the at least one light source driver comprises at least one LED driver.
 14. The system of claim 1, wherein the fixture input/output bus comprises: (i) a power port to provide DC power at the voltage of less than or equal to +40V; (ii) a common port to provide a reference voltage level; and (iii) at least one data port to receive the at least one digital control signal and to provide at least one digital reporting signal representative of the power consumption of the DCR lighting fixture.
 15. The system of claim 1, wherein the DCR lighting fixture further comprises: at least one sensor, in mechanical association with the fixture housing, to measure at least one fixture parameter; and a processor, in mechanical association with the fixture housing and operably coupled to the at least one light source driver and the fixture input/output bus, to transmit a measurement signal representative of the at least one fixture parameter via the fixture input/output bus.
 16. The system of claim 15, wherein the at least one fixture parameter comprises at least one of a temperature of the at least one light source, a bias voltage of the at least one light source, an operating current of the at least one light source, a color temperature of the at least one light source, and a color of the at least one light source. 